Adds tab indentation option for JSON files. (#4705)

crates/nu-command/src/formats/to/json.rs

@@ -22,6 +22,12 @@ impl Command for ToJson {
                 "specify indentation width",
                 Some('i'),
             )
+            .named(
+                "tabs",
+                SyntaxShape::Number,
+                "specify indentation tab quantity",
+                Some('t'),
+            )
             .category(Category::Formats)
     }
 
@@ -37,6 +43,7 @@ impl Command for ToJson {
         input: PipelineData,
     ) -> Result<nu_protocol::PipelineData, ShellError> {
         let raw = call.has_flag("raw");
+        let use_tabs = call.has_flag("tabs");
 
         let span = call.head;
         let value = input.into_value(span);
@@ -44,9 +51,11 @@ impl Command for ToJson {
 
         let json_result = if raw {
             nu_json::to_string_raw(&json_value)
+        } else if use_tabs {
+            let tab_count: usize = call.get_flag(engine_state, stack, "tabs")?.unwrap_or(1);
+            nu_json::to_string_with_tab_indentation(&json_value, tab_count)
         } else {
             let indent: usize = call.get_flag(engine_state, stack, "indent")?.unwrap_or(2);
-
             nu_json::to_string_with_indent(&json_value, indent)
         };
 

crates/nu-json/src/lib.rs

@@ -3,7 +3,8 @@ pub use self::de::{
 };
 pub use self::error::{Error, ErrorCode, Result};
 pub use self::ser::{
-    to_string, to_string_raw, to_string_with_indent, to_vec, to_writer, Serializer,
+    to_string, to_string_raw, to_string_with_indent, to_string_with_tab_indentation, to_vec,
+    to_writer, Serializer,
 };
 pub use self::value::{from_value, to_value, Map, Value};
 

crates/nu-json/src/ser.rs

@@ -946,6 +946,19 @@ where
     Ok(())
 }
 
+/// Encode the specified struct into a Hjson `[u8]` writer.
+#[inline]
+pub fn to_writer_with_tab_indentation<W, T>(writer: &mut W, value: &T, tabs: usize) -> Result<()>
+where
+    W: io::Write,
+    T: ser::Serialize,
+{
+    let indent_string = "\t".repeat(tabs);
+    let mut ser = Serializer::with_indent(writer, indent_string.as_bytes());
+    value.serialize(&mut ser)?;
+    Ok(())
+}
+
 /// Encode the specified struct into a Hjson `[u8]` writer.
 #[inline]
 pub fn to_writer_with_indent<W, T>(writer: &mut W, value: &T, indent: usize) -> Result<()>
@@ -972,6 +985,19 @@ where
     Ok(writer)
 }
 
+/// Encode the specified struct into a Hjson `[u8]` buffer.
+#[inline]
+pub fn to_vec_with_tab_indentation<T>(value: &T, tabs: usize) -> Result<Vec<u8>>
+where
+    T: ser::Serialize,
+{
+    // We are writing to a Vec, which doesn't fail. So we can ignore
+    // the error.
+    let mut writer = Vec::with_capacity(128);
+    to_writer_with_tab_indentation(&mut writer, value, tabs)?;
+    Ok(writer)
+}
+
 /// Encode the specified struct into a Hjson `[u8]` buffer.
 #[inline]
 pub fn to_vec_with_indent<T>(value: &T, indent: usize) -> Result<Vec<u8>>
@@ -1007,6 +1033,17 @@ where
     Ok(string)
 }
 
+/// Encode the specified struct into a Hjson `String` buffer.
+#[inline]
+pub fn to_string_with_tab_indentation<T>(value: &T, tabs: usize) -> Result<String>
+where
+    T: ser::Serialize,
+{
+    let vec = to_vec_with_tab_indentation(value, tabs)?;
+    let string = String::from_utf8(vec)?;
+    Ok(string)
+}
+
 /// Encode the specified struct into a Hjson `String` buffer.
 /// And remove all whitespace
 #[inline]